The first sharks appeared over 400 million years ago. It happened 200 million years before the dinosaurs.
Sharks have been found by scientists in all the oceans of our planet.
Sharks are a group of fish, known as cartilage. They consist entirely of cartilage.
For the reason that sharks are the least susceptible to cancer, scientists are studying their cartilage in hopes of finding a cure for this disease.
The first written mention of a shark attack is in the notes of Herodotus (ok.484-425 BC.). Based on these descriptions, hordes of "monsters" of the Persian fleet devoured sailors shipwrecked.
Blood - the main instigator of sharks to attack, they just a drop of blood on a thousand gallons of water, to smell the victim.
Jaw sharks are not attached to the base of the skull, allowing her a little push forward for a secure grip.
Before the invention of sandpaper, people have used the rough skin of a shark, called "sharkskin." Japanese War, especially swords wrapped around the handle of shark skin, so they do not slip from the hands.
Some fishermen catch sharks, cut off the fins for soup and throw the carcass live fish back into the sea. Mutilated sharks can not continue to swim and breathe and eventually die.
Sharks are 40-45 teeth. Nearby are a few (for replacement). When a tooth falls out or breaks down, you need only one day to replace the tooth movement following it into a series of forward. Over a lifetime, the shark can replace up to 30 thousand teeth. Moreover, the new teeth are always more, so Sharks age can look terrible.
The first use of the word "shark" in English was in 1569. Earlier, British sailors and fishermen used the term "salt" or Spanish word «tiburon».
Sometimes very strange things show whalers inside the stomach of sharks: shoes, chairs, nails, torpedoes, drums and so on.
Due to the aggressive nature of the family of gray sharks are sometimes referred to as "shark-gangsters».
Portuguese sharks live at a depth of 3, 5 kilometers under water.
About 2/3 of shark attacks on humans happen in the water at a depth of less than 2 meters.
Sharks often give warning signs before attacking: arch your back, raise your head.
More and more people die directly from bee stings and lightning strikes than from shark attacks. In the world, about 30 people die every year due to collisions with the sharks. Most often this occurs at a time when the shark chasing another victim and confuses the target.
Shark attacks recorded worldwide, but most often occurs around the popular beaches in North America (mainly Florida and Hawaii), Australia and South Africa.
Many shark species have a movable transparent membrane that during blinking movements to protect their eyes when they attacked the victim and eating.
Unlike fish, sharks do not have a swim bladder to keep your body afloat. However, for these purposes, they have large liver oil.
Fat shark liver previously served as the main source of vitamin A for humans. Basking shark liver weighs more than 1,000 kilograms and contains a special liquid that support the ballast body.
Contrary to popular belief, not the stomach shark is the largest organ on her body, in contrast to the liver, which can reach 25% of the weight of the entire body.
In the waters of Greenland sharks, which live in front of the special parasites that can glow in the dark water. Scientists believe that these luminous "helpers" attract prey into the jaws of shark.
Recent research oceanographers indicate that sharks cruising surface water can smell splashes of water masses from fighting nearby animals.
The largest fish caught by rod and reel, was a great white shark-eater. It weighed 1,200 kilograms and has a length of about 5 to 3 meters.
About 100 million sharks are killed each year. Shark teeth are used for necklaces, cartilage, fertilizer, leather is used to make skin, liver, applied in the manufacture of face cream and fins are going to prepare soup. Massacres sharks produce negative cascading effects on the global environment.
All living beings emit weak electrical signal at a time as they breathe or move. Some sharks, such as a hammer, can use these electrical impulses to catch prey. They catch signals from the victim via hundreds of tiny holes in the front of them, called Lorenzini ampoules.
There were times that the shark attacked the metal objects. This was because the metal emits weak electrical signals in contact with salt water, which was confusing sharks.
Most sharks are viviparous. Mother shark can give birth to up to 48 sharks in the same litter. Cubs are born tail first generally, and perhaps for some time are with the mother until they can fend for themselves.
Whale sharks - the leaders in the number of pups in one litter. For a time the light can appear several hundreds of small sharks.
The gestation period lasts for basking shark for more than two years. The longest period of pregnancy is the elephant (22 months).
When it comes time to give birth, the female shark loses appetite, not to be tempted to eat their own young.
Bony fish have dreams, but no sharks.
There are some fish that can not eat shark. When she bites them, they secrete special chemical in the shark's mouth that makes her jaw to unclench. Scientists are still trying to reproduce the formula of the substance to be used for the safety of people.
Native Americans in Florida used a great white shark teeth for arrowheads.
Shoes sharkskin wear 4 times less than that of other materials.
Some sharks, such as vobbegongovye, flat in shape so that in plan view they are merged as a part of the seabed.
Discovered in Japan in 1898, goblin shark has a long snout, beady eyes and pink-gray flabby skin. Some scientists because of the ugly kind of call it «Franlenshark».
Some sharks can hear prey in the water at a distance of 3 kilometers. It is best to recognize the low frequency sounds. But to hear high-frequency sounds dolphins are not able to, so hunt them they can not.
Nurse sharks - the laziest of all the sharks spend most of the day of rest on the sandy seabed, sometimes overlap. When they are hungry, they are like a giant vacuum cleaner sucking the prey from the surface and the bottom of the stones.
Sharks do not breathe through the nose, but it smells great feeling. Some individuals are able to smell one drop of blood to millions of parts, and to determine in which direction the odor.
Sharks do not have ears outside surface of the body, only on the inside of the head.
Sharks have rows of small holes on the sides of the body, called the lateral line organs. These bodies are sensitive to small movements in the water and are able to smell when other fish swim close to them.
Some sharks can bite hard enough to break a nose or a thick piece of steel.
The biggest and strongest of the known predatory fish in the sea - the great white shark (also known as "white death"). It grows up to 9 meters in length and is the only fish that is able to lift his head from the water to study the surfaces of objects. Her jaw is six times stronger than the wolf. 30-50% of all fatal attacks on people committing White Shark.
The second most dangerous sharks in the world is the tiger shark. Sometimes called the "dustbin of the sea", because it eats everything it sees, including dead animals, cans, car tires and other waste. In the stomach of one of them was even found the remains of a chicken coop with bones and feathers of birds.
People have very little chance of survival after a shark attack. One of the most striking cases occurred in Tasmania (Australia) in 1993. Terry Cartwright died instantly after the attack, 5-meter great white shark, and his family watched in horror this event with a boat. They last saw his body in the mouth of a shark. Part of suit legs and Terry were later found nearby.
Sharks may have evolved from jawless fish such as lampreys.
Shark "thrasher" uses its long tail to hunt fish. The tail is half the length of her body. She uses it to stun their prey.
Sharks can use the Earth's magnetic field for its ad hoc bodies, which act as a compass to navigate the ocean.
Until the nineteenth century, some inhabitants of the islands in the South Pacific felt the shark gods, and exalted human sacrifices for them.
In the Solomon Islands, it is believed that when people die, their ghosts inhabit the bodies of sharks.
Downed pilots and shipwrecked sailors sometimes used the special protection of sharks. She hid the shape of the face and kept out of reach of the shark body odors.
While the ostrich lays the largest egg in the world on land, the whale shark lays the largest egg in the world under the water. Egg whale shark is 35 centimeters in diameter, was found in the Gulf of Mexico in 1953.